As a method for dehumidification of air, it is one way to compress and cool the air. This invention belongs to a method for dehumidification of air according to this system.
In case of cooling the air, lower limit of cooling is considered to be down to 0.degree.C to avoid blocking by freezing of the path of air, and the nearer the cooling temperature to 0.degree.C, the more the moisture in the air changes to water drop, so that the effect of dehumidification becomes larger as the water drop is removed. For such a case, it becomes necessary to use a refrigerator usually.
On the other hand, the air to be used in spray painting or the like is better when the humidity of air is lower, and since it is used intermittently, the refrigerator for cooling medium complying with large amount of temporary load will be available with smaller horsepower, when heat exchange is effected by way of water or the like, which has large heat capacity, between the cooling medium and the air (rather than the direct heat exchange through pipe wall), in consideration of the load of cooling medium complying with said intermittent demand of air.